1. Field of Invention
The invention relates to a fan system and a starting method thereof and, in particular, relates to a fan system and a starting method thereof capable of starting fans synchronously or in sequence.
2. Related Art
With the high development of the technology, the requirements on the functions of an electronic apparatus are getting higher and higher, the number of the used electronic elements and the degree of integration are getting higher and higher, and the need to dissipate heat is increased. Therefore, the heat dissipating function directly influences the reliability and the lifetime of the electronic apparatus.
A fan is frequently used to serve as a heat-dissipating device, and the number of fans is usually increased or decreased according to different requirements of the corresponding clients. In addition, the rotating speed of each fan in the fan system is controlled and driven by a controlling device or a controlling chip so that the rotating speed of the fan may be adjusted according to the actual operating conditions of the customer system.
As shown in FIG. 1, a conventional fan system is electrically connected to a customer system end SB1. The fan system includes a hot-swap controlling device 11, a controlling device 12 and a fan device 13. Usually, the customer system end SB1 provides main power MP1, sub-power SP1, and a connector C1 for transmitting a first driving signal S01 generated by the main power MP1 and a second driving signal S02 generated by the sub-power SP1 to the fan system.
The hot-swap controlling device 11 has a plurality of hot-swap elements 111 and 112 electrically connected with each other, and a plurality of pins 113. The hot-swap elements 111 and 112 are electrically connected to the customer system end SB1, the controlling device 12 and the fan device 13, and receive the first driving signal S01 and the second driving signal S02, respectively.
The controlling device 12 is a digital signal processor or a microprocessor, and the hot-swap element 112 transmits the second driving signal S02 to start the controlling device 12.
The fan device 13 is electrically connected to the controlling device 12, and has a plurality of fans 131 and a plurality of isolating circuits 132. The hot-swap elements 111 transmit the first driving signals S01 to start the fans 131, respectively, while the isolating circuits 132 are electrically connected to and between the controlling device 12 and the fans 131 to transmit a pulse width modulation (PWM) signal P generated by the controlling device 12 to the fans 131 so that rotating speeds of the fans 131 are changed according to the PWM signal P.
In general, the fan system has to provide the sufficient heat dissipating requirement for the customer system end SB1 in any state. When one of the fans 131 of the fan system is damaged, the fan can be immediately replaced in a hot-swap manner through the hot-swap element 111 so that the heat dissipating requirement of the customer system end SB1 is maintained. However, the hot-swap elements 111 and 112 correspondingly connected to the main power MP1 and the sub-power SP1 of the customer system end SB1 are powered on independently. When the user improperly swaps the fan, the pins 113 of the hot-swap controlling device 11 are easy to be bent, and the problem of the poor contact may rise due to the reduced terminal with the connector C1.
In addition, the motor (not shown) of the fan 131 is the dynamic inductive load, and a high start current is required to start the fan 131 from the stationary state to the stable state. At the moment when the fan system is being started, an inrush current, a spike voltage or a spike noise may be generated between the fan system and the connector C1 of the customer system end SB1, or even a spark phenomenon (i.e., an electric arc) is generated, thereby damaging the customer system end SB1 or the fan system.
In addition, the pins 113 of the hot-swap controlling device 11 are now made into a floating connector, as shown in FIG. 2, or a floating board (not shown) to ensure the pins 113 to contact the connector C1 instantaneously. However, this method still cannot effectively and completely suppress the generation of the spike noise on the pins 113. In addition, when the hot-swap is being performed, the positive or negative spike noise generated by the hot-swap elements 111 tends to damage the small-signal electronic element (not shown) of the fan system through the grounding circuit of the main power MP1 and the pins 113. Thus, the isolating circuits 132 are usually provided for the purpose of protection. In addition, if the hot-swap elements 111 are frequently used, the terminals of the pins 113 tend to have the poor contact due to the oxidation, and the lifetime of each of the hot-swap elements 111 tends to be shortened so that the quality of the fan system 1 is deteriorated.
In addition, the functions of the customer system end SB1 becomes more complicated, the functional requirements on the fan system 1 are getting higher and higher. However, the first driving signal S01 and the second driving signal S02 are simultaneously inputted and then the fans 131 are simultaneously started in the conventional fan system 1, and the starting method of the fan system 1 cannot be changed according to different requirements and different occasions at the customer system end SB1.
Therefore, it is an important subject to provide a fan system and a starting method thereof, wherein a customer system end and the fan system can be simultaneously protected and fans may be synchronously or started in sequence according to the requirement at the customer system end.